1. Field of the Invention
This invention relates generally to the fields of immunology, inflammation, and tumor immunology. More specifically, the present invention relates to biologically active biomimetic molecules comprising immunoglobulin Fc domains, compositions comprising such biomimetics, and methods of using such biomimetics.
The invention also relates to the treatment and prophylaxis of pathological conditions mediated by monocyte-derived cells, and more particularly to the use of stabilized functional portions of IgG Fc fragments for such treatment and prophylaxis.
2. Description of the Background Art
Immune globulin products from human plasma have been used since the early 1950's to treat immune deficiency disorders and more recently, and more commonly, for autoimmune and inflammatory diseases.
Initially, immune globulin products were administered by intramuscular injection. More recently, intravenous immune globulin (IVIG) has been used and was initially shown to be effective in treatment of the autoimmune disease idiopathic thrombocytopenic purpura (ITP) (Imbach P, Barandun S, d'Apuzzo V, et al: High-dose intravenous gammaglobulin for idiopathic thrombocytopenic purpura in childhood. Lancet 1981 Jun. 6; 1(8232): 1228-31). Human IVIG (referred to herein as “hIVIG”) is a formulation of sterile, purified immunoglobulin G (IgG) products manufactured from pooled human plasma that typically contains more than 95% unmodified IgG, with only small and variable amounts of immunoglobulin A (IgA) or immunoglobulin M (IgM) (see, for example, Rutter A, Luger T A: High-dose intravenous immunoglobulins: an approach to treat severe immune-mediated and autoimmune diseases of the skin. J Am Acad Dermatol 2001 June; 44(6): 1010-24). Today the single most common clinical use of hIVIG is in the treatment of ITP.
While hIVIG has been an effective clinical treatment, there are several shortcomings to hIVIG formulations, including the potential for inadequate sterility, the presence of impurities, lack of availability, and lot-to-lot variation. In particular hIVIG preparations can vary greatly in their immunoglobulin A (IgA) content which can be of concern because IgA can cause allergic and anaphylactic reactions in IgA-deficient recipients.
In view of the negative aspects of hIVIG, there exists a need for an improved means of treating autoimmune and inflammatory diseases.
In addition, multiple pathological conditions of a wide variety of types are mediated by cells derived from monocytes. A simple therapeutic and/or prophylactic agent for use in many, if not all, such conditions would be invaluable.